High-performance Ajax Applications

Location: Salon A-D Level: Intermediate
Average rating: ***..
(3.00, 1 rating)

In the past few years, Ajax has become very popular because it has enabled developers to build more complex web applications. However, in the rush to push the browser to new limits, we have created a monster.

While the original goal of Ajax was to make web applications more responsive by not reloading the entire document every time something changed on the page, the use of DHTML has sometimes made the overall experience more sluggish because browsers were never really designed as application platforms, occasionally performing poorly while executing seemingly simple tasks.

Furthermore, many “traditional” application developers have recently moved to the browser, applying their existing skills to a radically different platform, sometimes with disastrous consequences.

Building on Yahoo!‘s Exceptional Performance Rules, this presentation discusses much of the Ajax community’s common wisdom, and describes in great details what it takes to develop high performance Ajax applications. It includes a description of many different techniques, patterns, and best practices that could give your application a little “kick in the rear.”

Photo of Julien Lecomte

Julien Lecomte


I am currently an engineer on Yahoo!‘s DHTML Evangelist team, a group that provides architectural assistance to Yahoo! developers on the design and implementation of rich interactions in the browser, working alongside the famous Douglas Crockford and Iain Lamb (co-founder of OddPost) Among other things, I have worked extensively on Yahoo!’s new Mail application, and I am the author of the YUI Browser History Manager and the YUI Compressor. I have also contributed to many different projects including Yahoo! Search and Yahoo! Calendar.

Prior to working at Yahoo, I was a Senior Software Engineer at Scalix (now part of Xandros), where I spent a couple of years developing their web client. Prior to joining Scalix, I was a software engineer at easyplanet where I worked on a consumer VoIP application based on the OpenH323 library.

During my spare time, I like to run on trails, practice amateur astronomy, work on my hobby operating system — Simplix — enjoy some good wine and foods, and travel to exotic destinations with my beautiful wife.

In 2001, I obtained a Master’s degree in computer science from Supelec, a leading engineering institute in France.


  • Akamai
  • Google
  • Hyperic
  • Sun Microsystems
  • 3Tera, Inc
  • Coradiant
  • Keynote Systems
  • Limelight Networks, Inc.
  • OpSource
  • TechRepublic

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